Multipurpose host system for invasive cardiovascular diagnostic measurement acquisition and display

ABSTRACT

A multifunctional invasive cardiovascular diagnostic measurement host is disclosed that interfaces a variety of sensor devices, such as guide wire-mounted pressure sensors, flow sensors, temperature sensors, etc, and provides a multi-mode graphical user interface providing a plurality of displays in accordance with the various types of sensors and measurements rendered by the sensors.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/555,556 filed on Nov. 1, 2006, which is a divisional of U.S. patentapplication Ser. No. 10/151,423 filed on May 20, 2002, now U.S. Pat. No.7,134,994, each of which is hereby incorporated by reference in itsentirety.

AREA OF THE INVENTION

The present invention generally relates to the area of diagnosticmedical equipment, and more particularly to diagnostic devices foridentifying and/or verifying efficacy of treatment of problematicblockages within coronary arteries by means of sensors mounted upon theend of a flexible elongate member such as a guide wire.

BACKGROUND OF THE INVENTION

Innovations in diagnosing and verifying the level of success oftreatment of cardiovascular disease have migrated from external imagingprocesses to internal, catheterization-based, diagnostic processes.Diagnosis of cardiovascular disease has been performed through angiogramimaging wherein a radiopaque dye is injected into a vasculature and alive x-ray image is taken of the portions of the cardiovascular systemof interest. Magnetic resonance imaging (MRI) has also been utilized tonon-invasively detect cardiovascular disease. Diagnostic equipment andprocesses also have been developed for diagnosing vasculature blockagesand other vasculature disease by means of ultra-miniature sensors placedupon a distal end of a flexible elongate member such as a catheter, or aguide wire used for catheterization procedures.

One such ultra-miniature sensor device is a pressure sensor mounted uponthe distal end of a guide wire. An example of such a pressure sensor isprovided in Corl et al. U.S. Pat. No. 6,106,476, the teachings of whichare expressly incorporated herein by reference in their entirety. Suchintravascular pressure sensor measures blood pressure at various pointswithin the vasculature to facilitate locating and determining theseverity of stenoses or other disruptors of blood flow within thevessels of the human body. Such devices are presently used to determinethe need to perform an angioplasty procedure by measuring blood pressurewithin a vessel at multiple locations, including both upstream anddownstream of a stenosis and measuring a pressure difference thatindicates the severity of a partial blockage of the vessel.

In particular, a guide wire mounted pressure sensor is utilized tocalculate fractional flow reserve (or “FFR”). In the coronary arteries,FFR is the maximum myocardial flow in the presence of stenosis dividedby the normal maximum myocardial flow. This ratio is approximately equalto the mean hyperemic (i.e., dilated vessel) distal coronary pressure Pddivided by the mean arterial pressure Pa. Pd is measured with a pressuresensor mounted upon a distal portion of guide wire or other flexibleelongate member after administering a hyperemic agent into the bloodvessel causing it to dilate. Pa is measured using a variety oftechniques in areas proximal of the stenosis, for example, in the aorta.

FFR provides a convenient, cost-effective way to assess the severity ofcoronary and peripheral lesions, especially intermediate lesions. FFRprovides an index of stenosis severity that allows rapid determinationof whether an arterial blockage is significant enough to limit bloodflow within the artery, thereby requiring treatment. The normal value ofFFR is about 1.0. Values less than about 0.75 are deemed significant andrequire treatment. Treatment options include angioplasty and stenting.

Another such known ultra-miniature sensor device is a Doppler blood flowvelocity sensor mounted upon the end of a guide wire. Such device emitsultrasonic waves along the axis of a blood vessel and observes aDoppler-shift in reflected echo waves to determine an approximation ofinstantaneous blood flow velocity. A Doppler transducer is shown in Corlet al. U.S. Pat. No. 6,106,476 on a guide wire that also carries apressure transducer. Such devices are presently used to determine thesuccess of a treatment to lessen the severity of a vessel blockage.

In particular, a Doppler transducer sensor is utilized to measureCoronary Flow Reserve (or “CFR”). CFR is a measure for determiningwhether a stenosis is functionally significant after treatment (e.g.,post-angioplasty). CFR comprises a ratio of the hyperemic average peakvelocity of blood flow to the baseline (resting) average peak velocity.Instantaneous peak velocity (IPV) is the peak observed velocity for aninstantaneous Doppler spectrum provided by a Doppler transducer. Anexemplary method of calculating an average peak velocity (APV) comprisesaveraging a set of IPV's over a cardiac cycle.

A known technique for determining whether an angioplasty was effectivewas to perform angioplasty, wait a few days, then perform thaliumscintigraphy (imaging). If the angioplasty procedure was not effective,then re-intervention was performed and the lesion was again treated viaangioplasty. On the other hand, using CFR, a flow measurement is takenimmediately after angioplasty or stenting. The flow measurement isutilized to determine whether adequate flow has been restored to thevessel. If not, the balloon is inflated without the need for secondaryre-intervention. A normal CFR is greater than about 2 and indicates thata lesion is not significant. Lower values may require additionalintervention. In addition to being used post-treatment to determine theefficacy of treatment, CFR may be measured prior to treatment todetermine if treatment is required.

A guide wire combination device, comprising a pressure sensor and a flowsensor having substantially different operational characteristics, wasdisclosed in the Cori et al. U.S. Pat. No. 6,106,476. While it has beenproposed within the Corl et al. U.S. Pat. No. 6,106,476 to combinepressure and flow sensors on a single flexible elongate member, theprior art does not address how such a combination sensor is coupled toconsoles that display an output corresponding to the signals provided bythe flexible elongate member corresponding to the sensed pressure andflow within a vessel. Indeed, the relevant art comprises special-purposemonitors having static display interfaces that display a static set ofparameters corresponding to a particular fixed set of diagnosticmeasurements (e.g., an aortic pressure and a pressure taken from alocation proximate a stenosis). Thus, one type of monitor is utilized toprocess and display sensed pressure within a blood vessel. Another typeof monitor provides output relating to blood flow within a vessel. Asnew intravascular diagnostic devices are developed, yet otherspecial-purpose monitors/consoles are developed to display to aphysician the sensed parameters.

There is substantial interest in simplifying every aspect of theoperating room to reduce the incidence of errors. As one can imagine,the aforementioned intravascular pressure sensors are utilized inoperating room environments including many types of sensors andequipment for diagnosing and treating cardiovascular disease. Clearly,the room for error is very limited when performing such activities.Notwithstanding the interest to keep equipment and operations simple,there exists a variety of different sensors that are potentiallyinserted within a human vasculature to diagnose arterial disease (e.g.,blockages) and/or monitor vital signs during a medical procedure. Theapproach taken in the field of interventional cardiac imaging has beento provide multiple, special-purpose monitor consoles. Each monitor typeis linked to a particular type of sensor device.

In a known prior intravascular pressure sensor-to-physiological monitorinterface arrangement, marketed by JOMED Inc. of Rancho Cordova, Calif.,a physiology monitor receives and displays, on a permanently configureddisplay interface, a set of pressure values corresponding to twodistinct pressure signals that are received by the monitor. A firstpressure signal is provided by an aortic pressure sensor, and a secondpressure signal corresponds to a pressure sensed by a distally mountedsolid-state pressure sensor mounted upon a guide wire. The displayinterface of the monitor is permanently configured to output parametervalues corresponding to those two signals. Thus, if display of, forexample, a flow signal value is desired, then a separate monitor, suchas JOMED Inc.'s FloMap, is used.

SUMMARY OF THE INVENTION

The present invention provides addresses a need to provide a flexible,multipurpose host system for processing and displaying signals renderedby invasive cardiovascular sensors to reduce the amount of equipment andcomplexity of procedures for diagnosing and determining the efficacy oftreatment of cardiovascular stenoses.

In particular, the present invention comprises a multipurpose hostsystem that facilitates invasive cardiovascular diagnostic measurementacquisition and display. The host system includes a number ofmodularized components. The host system includes an external inputsignal bus interface for receiving data arising from cardiovasculardiagnostic measurement sensors such as, for example, pressuretransducers, Doppler flow transducers, temperature sensors, pH sensors,optical sensors, etc.

The host system also includes a plurality of measurement processingcomponents for receiving data of particular sensor types. The processingcomponents render diagnostic measurement parameter values according tothe received data arising from various types of attached sensors. In aparticular embodiment, the processing components are instantiated atstartup time from component modules that are dynamically integrated intothe host system. This allows the functionality of the host system to beextended to include new types of sensors without requiring an overhaulof the existing system software.

The host system also includes a multi-mode graphical user interfacehost. The interface host comprises a set of diagnostic measurement userinterfaces. The output interfaces are integrated with the processingcomponents and carry out displaying, on a graphical user interface a setof output values corresponding to parameter values rendered by theprocessing components.

BRIEF DESCRIPTION OF THE DRAWINGS

While the appended claims set forth the features of the presentinvention with particularity, the invention, together with its objectsand advantages, may be best understood from the following detaileddescription taken in conjunction with the accompanying drawings ofwhich:

FIG. 1 is a schematic drawing depicting a system for conducting invasivecardiovascular diagnoses including an external input signal interfacefor receiving diagnostic parameter values of multiple types and amultimode graphical user interface for presenting the values accordingto a user-selected one of the multiple display modes;

FIG. 2 is a schematic drawing depicting an exemplary architecture of thesystem depicted in FIG. 1;

FIG. 3 depicts an exemplary generic graphical user interfacespecification upon which a set of graphical displays are based inaccordance with the various graphical user interface modes supported bya host system embodying the present invention;

FIG. 4 depicts an exemplary graphical user interface for a patient dataentry sub-screen of a system display mode of the host system;

FIG. 5 depicts an exemplary graphical user interface for a user/patientdata entry sub-screen of a system display mode of the host system thatincludes a keyboard;

FIG. 6 depicts an exemplary graphical user interface for a systemconfiguration sub-screen of a system display mode of the host system;

FIG. 7 depicts an exemplary graphical user interface for a setupsub-screen of a system display mode of the host system;

FIG. 8 depicts an exemplary graphical user interface for acommunications sub-screen of a system display mode of the host system;

FIG. 9 depicts an exemplary graphical user interface for a setupsub-screen of a pressure display mode of the host system;

FIG. 10 depicts an exemplary graphical user interface for a displaysub-screen of a pressure display mode of the host system;

FIG. 11 depicts an exemplary graphical user interface for a setupsub-screen of a flow display mode of the host system;

FIGS. 12 a-e depict an exemplary graphical user interface for a displaysub-screen of a flow display mode of the host system;

FIG. 13 depicts an exemplary graphical user interface for a combinationflow and pressure display mode of operation of the host system;

FIG. 14 is a flowchart summarizing a set of steps for carrying out acoronary flow reserve measurement using the multipurpose host systemdescribed herein;

FIG. 15 is a flowchart summarizing a set of steps for carrying out afractional flow reserve measurement using the multipurpose host systemdescribed herein; and

FIG. 16 is a flowchart summarizing a set of steps for carrying out aproximal/distal pressure ratio measurement using the multipurpose hostsystem described herein.

DETAILED DESCRIPTION OF THE DRAWINGS

A multipurpose host system for invasive cardiovascular diagnosticmeasurement acquisition and display provides an advantage of the priorknown systems in regard to its ability to present multiple user displayinterfaces. Each of the display interfaces corresponds to a particularpurpose for which the multipurpose host is currently configured based,for example, upon one or more sensor devices communicatively coupled toits external signal interface. The host system is used, for example, inconjunction with interventional cardiology, e.g., angiography, orinterventional procedures, e.g., angioplasty, to evaluate thehemodynamic status of an arterial blockage.

With reference to FIG. 1, a multipurpose host system 100 is, by way ofexample, a personal computer architecture-based system for assessingreal-time invasive cardiovascular parameters from within a blood vessel(e.g., blood pressure and flow measurements). The multipurpose hostprocesses input signals from multiple micro-miniature guide wire-mountedsensors (e.g., Doppler and pressure transducers) to produce real-timemeasurements, display various waveforms and derived parameters, andoutput high-level voltages proportional to calculated parameter values.The devices that supply the various data input signals are representedby pressure input 102, velocity flow input 104, volume flow 106, andtemperature input 108. In an embodiment of the invention, the devicesthat provide the input to the host system 110 are presently used inexisting, special-purpose processing boxes. This set is exemplary, asthose skilled in the art will readily appreciate in view of thisdisclosure that alternative systems advantageously receive and processsuch diagnostic inputs as pH, ultrasound and light-based cross-sectionalimages of a vessel, biochemical markers, light spectrometry for tissuecharacterization, etc. It is further noted that the displayed output ofthe host system 100 is not limited to producing the measured parameters.Rather, the various modes of the host system 100 are capable ofsynthesizing generalized measures of physiological status (e.g., whethera blockage is severe and needs treatment) based upon the input parametervalues.

The host system 100 operates in a plurality of modes, and each modeincludes its own distinct graphical interface (rendered on graphicaloutput display 110) and input parameter values (provided via aperipheral component interconnect (PCI) card 112) corresponding toparticular sensor types. The PCI card 112 includes, by way of example, adigital signal processor (DSP) that samples data provided by thecommunicatively coupled input sensors and processes the sampled data torender digital data in a format expected by higher level components ofthe host system 100. Exemplary processes performed by the DSP include:A/D and D/A conversions, FFTs, level shifting, normalizing, and scaling.After processing the data, it is stored in a dual port RAM accessed, viathe PCI bus of the host 100, by higher level application processesexecuting on the host system 100.

In the exemplary embodiment, input sensor types driving the outputdisplays include pressure, flow, and temperature sensors mounted upon aflexible elongate member including combinations thereof placed, forexample, upon a single guide wire or catheter. In fact, the flexiblemodule-based architecture (see, FIG. 2) of the exemplary host system110, which supports simultaneous display of multiple distinct types ofinput signals on a single graphical user interface, is particularly wellsuited for such combination devices since their output can besimultaneously monitored on a single interface even though modules thatprocess the sensor inputs execute independently within the host system100.

The exemplary host system 100 operates in pressure, flow, andcombination (pressure/flow) modes. Though not essential to theinvention, operation of each mode is preferably independent of the othermodes, and each diagnostic display mode is driven by a designated set ofparameter generation modules associated with particular input signalsreceived by the host system from a communicatively coupled sensor. Thepressure mode provides the user with a selection of calculated/derivedparameters such as for example: proximal-distal pressure gradient,distal/proximal pressure ratio, normalized pressure ratio, andfractional flow reserve (normalized pressure ratio under hyperemicconditions). In an exemplary embodiment, the flow mode is divided intothree operational modes: peripheral, coronary, and research. Theperipheral mode acquires measurements in the cerebral or peripheralvasculature. The coronary mode acquires measurements in the coronaryarteries. The research mode provides a superset of peripheral andcoronary modes plus additional parameters that may be of interest in aclinical research environment. The combination mode allows parametersassociated with pressure and flow modes to be displayed simultaneouslyon a single graphical display.

In the illustrative embodiment of the invention, the graphical displayinterface 110 depicts calculated pressure and flow information on astrip chart graph on a graphical user interface display. The currentvalues are, for example, displayed numerically as well. The graphscrolls as new information is calculated and added. A graphicallydisplayed to control enables a user to freeze the scrolling graphs andscroll backwards to view previously displayed portions of the scrollinggraph. Additional display methods and techniques will be apparent tothose skilled in the art.

The host system 100 embodies an extensible, component-basedarchitecture, and thus the host system 100 supports a virtuallylimitless number of operating modes for processing and renderinggraphical display output corresponding to an extensible set of inputsignals provided by sensors measuring a variety of types andcombinations thereof. The host system 100 is modularized to supportreceiving and processing signals in a variety of formats from a varietyof instruments. In a particular exemplary embodiment of the invention,the host system 100 relies on transducers and external diagnosticinstrumentation to: (1) process the raw sensor information rendered bytransducers/sensors inserted within a patient and (2) provide theinformation to the host 100 in particular digital or analog formats. Thehost system 100's capabilities are extendable, by way of example throughenhancements to a currently installed peripheral component interconnect(PCI) board 110 or the addition of new PCI boards, to include additionalsignal processing capabilities. In an exemplary embodiment, transducerson the guide wire (patient isolated) provide low-level signals for bloodvelocity, flow, and pressure. A standard external pressure transducer(patient isolated) may be integrated with the host system to providelow-level aortic pressure. A high-level ECG signal input to the hostprovides synchronization for calculations (not patient isolated).

The interface of the host system 100 comprises a number of additionalinterfaces supporting the transfer and storage of information relatingto the operation of the host system. Data storage device 114, forexample, a CD-RW or a DVD-RW drive, is utilized to upload new softwareand store patient data processed and displayed during adiagnostic/treatment procedure. A network interface 116 provides remoteaccess for performing functions similar to those provided by the datastorage device 114. An audio input 118 enables annotation of inputrecords by a user. A printer 120 facilitates printing out labels and/orcompiled data from a diagnostic/treatment procedure. The set ofperipheral/interface components identified in FIG. 1 is exemplary. Asthose skilled in the art will readily appreciate there exist a vastvariety of I/O devices that can be advantageously incorporated into thehost system 100 to enhance its utility.

Having described the peripheral components and external interfaces of anexemplary host system 100, attention is now directed to FIG. 2 thatdepicts an exemplary internal architecture of the host system 100 thatfacilitates operation of the host 100 in a variety of display modesassociated with a variety of sensed invasive cardiovascular parameterssuch as temperature, pressure and blood flow within an artery. The PCIcard 112 represents a highly flexible component of the host system 100architecture. The PCI card 112 includes a set of external sensorinterface circuits for transmitting power and excitation signals tosensor devices and receiving sensed parameter values illustrativelydepicted in FIG. 2. In the illustrative example, the PCI card 112includes both analog and digital input and output signals. Analog outputsignals are driven by the PCI card 112 output circuitry according tocontrol commands supplied by high level user mode processes executing onthe host system 100.

It is noted that a wide variety of sensor types are known and the hostsystem 100 is not limited to any particular type of sensor input. To thecontrary, the present host system 100 is intended to provide a broad,extensible, multipurpose platform upon which a wide variety ofapplication-specific modules are capable of processing and displayingsensor data rendered by a variety of sensor types and combinations ofthe sensor types including those described, by way of example herein.

The PCI card 112 includes a digital signal processor (or DSP) 200 thatoperates as a special purpose co-processor on the host system 100. TheDSP 200 receives digital samples corresponding to signals received viaexternal inputs to the PCI card 112, and carries out appropriateprocessing (e.g., FFT, filtering, scaling, normalizing, etc.) on thedigital/digitized data samples. Thereafter, the processed data is placedinto a dual port RAM within the PCI bus interface 202.

Kernel mode drivers 204 executing on the host 100 facilitatecommunicating commands and data between the PCI card 112 and a set ofuser mode processes 206 that drive input parameter values for themultiple graphical user interface modes supported by the host system100. The kernel mode drivers 204 communicate with the PCI bus interface202 according to a set of methods defined by a PCI Application ProgramInterface (API) 212. The kernel mode drivers 204 access PCI registersand ports on the PCI bus interface 202 to extract processed sensor dataand to issue control commands to the PCI card 112. The kernel modedriver 204 carries out other desired driver functionality includingissuing startup and diagnostic commands to the PCI card 112 and enablingand disabling particular inputs and outputs of the PCI card 112. In anembodiment of the invention, the PCI API 212 are sufficientlygeneralized such that the PCI card 112 can be replaced by a differentPCI card that includes a different set of input/output interfaceswithout requiring replacement of the presently installed kernel modedrivers 204—though reconfiguration may be required to set up newconnections between the kernel mode drivers 204 and sources andrecipients of data and commands in the PCI interface 202.

The kernel mode drivers 204 also includes functional components thatrespond to interrupts generated by the PCI card 112 (e.g., data ready,hardware errors, etc.). Other exemplary functions performed by thefunctional components of the kernel mode drivers 204 include detectingPCI installed devices, retrieving information about installed devices,read/write data from/to PCI configuration registers, execute a singleread/write operation to an I/O port or memory on the PCI interface 202,set up interrupt handling, allocate resources, and store sensordevice-specific data. The functional driver module 214 responds to newdata available for submission to user mode processes (described hereinbelow) responsible for rendering input data that drives the user modegraphical user interface (e.g., graphs, instantaneous parameter valuesfor pressure and flow velocity, etc.).

The user mode level of the host 100 embodies a modular/component basedarchitecture. The modular architecture provides a high degree offlexibility in developing and incorporating new sensor types, andcorresponding graphical user interfaces, into the multimode host userinterface. The user mode processes 206 include an extensible COM-basedhost application 222 that is responsible for presentation of a multipleinterface mode graphical user interface (preferably with touch screenfunctionality). At startup, the host application 222 instantiates a setof user interface mode objects from a registry of available userinterface mode object classes. Examples of such user interface modeobjects include Pressure, Flow, and Combination. Extension of a base setof graphical user interfaces to include new user interface modes, suchas Temperature and pH, is achieved by installing one or more new DLLscontaining a user interface mode class objects corresponding to new userinterface modes. In an embodiment of the invention, a separate userinterface mode component object is provided for each distinct userinterface mode supported by the host application 222.

The set of user mode processes 206 also include a set of measurementprocessing components 224. In an embodiment of the invention, eachmeasurement processing component corresponds to a particular sensor. Themeasurement processing components 224 are instantiated from a set ofsensor-specific component object model (COM) objects provided by one ormore dynamically linked library (DLL) files. Each sensor-specificcomponent is executed as a thread within a same process, oralternatively, as a separate process. Thus, a malfunction in onesensor-specific component will not affect the operation of properlyoperating sensor-specific components. The above-described COM approachto sensor data handling at the user mode level 206 also enables the setof input sensors and corresponding displayed interfaces to be readilyextended by installing new DLLs from which the host system 100instantiates COM objects corresponding to the new sensor input types.The illustrative host system 100 depicted in FIG. 2 includes thefollowing sensor-specific components: pressure 226, flow velocity 228,flow volume 230, temperature 232, and auxiliary 234. An exemplary inputprocessed by the auxiliary component 234 is a position signal renderedby one or more displacement sensors (e.g., a rotational position, alengthwise position along a vessel). The sensor-specific components aredescribed further herein below. Additional component types of componentsin the set of measurement processing components 224 (e.g., temperature,pH, etc.) in accordance with alternative embodiments of the host system100.

In the illustrative embodiment of the invention, the set ofsensor-specific components is extensible. Thus, when a new sensor typeof sensor is developed for the host system 100, the set of measurementprocessing components 224 is extended by developing and dynamicallyincorporating a new sensor-specific component object.

Thereafter, integration of the new sensor-specific component object isachieved by properly identifying the object as a member of the class ofsensor-specific measurement processing components 224 that areinstantiated when the system 100 starts up.

The set of measurement processing components 224 receive sensor dataretrieved from the PCI interface 202 and drive inputs to particular onesof the graphical user interface display modes supported by the hostapplication 222. The communications with the kernel mode processes 204are carried out via a sensor component API 238 which enables themeasurement processing components 224 to communicate with an applicationlogic component 240. The sensor component API 238 methods are functionoriented. An exemplary set of such methods in the sensor component API238 include: setting operational states of the sensors, extractingsensor data, issuing control commands to the PCI card 112configuring/controlling operation of the sensors. The application logiccomponent 240 translates calls issued by ones of the set of measurementprocessing components 224 into calls to the kernel mode drivers 204. Theapplication logic component 240 passes sensor data (originating from thePCI interface 202) from the kernel mode drivers 204 to the measurementprocessing components 224. Communications between the application logiccomponent 240 and the kernel mode drivers 204 accessing the DSP 200 andthe PCI interface 202 are carried out in accordance with a digitalsignal processing (DSP) API 242. The methods of the API 242 are hardwareoriented, and include, by way of example: handling an interrupt, writingDRAM, writing DRAM, starting and stopping particular DSP functionsrelating to particular sensors and/or interfaces.

Having described the general architecture of the host system 100,attention is now directed to the multi-mode graphical user interfacesupported by the host application 222. It is further noted that the userinterfaces preferably are augmented by touch screen functionality. Thevarious display interface modes, while different, preferably share acommon look and feel based upon a generic graphical user interfacespecification. FIG. 3 depicts an exemplary generic graphical userinterface specification upon which a set of graphical displays are basedin accordance with the various graphical user interface modes supportedby the host application 222.

The exemplary graphical user interface architecture consists of threededicated data display regions. A first region 300 is reserved fordisplay of system and patient information. A second region 302 isreserved for system messages. A third region contains a set ofhierarchical screens including a set of functionally related display andinteractive components accessed, by way of example, by selection of oneof a set of tabs 306.

The first region 300 is persistent and is displayed during all modes ofoperation of the host application 222. In an embodiment of theinvention, the first region 300 includes one or more of the followingfields relating to a patient/session: Patient Name, Patient ID—customerspecific identification number, Physician—name of the attendingphysician, Institution—name of the client institution using the system,Date/Time—current date and time, and a branding logo.

The second region 302 of the exemplary graphical user interface generallayout is reserved to display system messages. The second region 302also persists for all modes of operation. The second region 302includes, by way of example, the following fields relating to thedisplay of messages generated by the host system: Current status—amessage indicating the current operation state or status of the unit;Warning events—a message advising the user of a potential problem andpossible remedy; Error events—a message notifying the user of a systemerror and possible corrective action; and System Mode—a messagenotifying a user of the current mode of operation of the host 100.

A third region 304, by way of example, is reserved to display parametersand input/output data fields according to a current mode of operation ofthe host 100 and display mode of the host application 222. The thirdregion 304 is not persistent. Rather, the content of the third region304 is determined by a particular use mode within which the hostapplication is operating. In an embodiment of the invention, the thirdregion 304 operates in one or more of the following modes: System,Pressure, Flow, and Combo (Combination). Additional modes aresupported/displayed by the host application 222 in to accordance withalternative embodiments of the host 100. Such additional modesaccommodate, for example, displaying additional sensor-provided/derivedoutput parameters (e.g., temperature, pH, etc.) or new sets/combinationsof previously existing output parameters display elements. Each modeincludes at least a second level of screens once the mode is selected bymeans of the tabs 306.

Turning now to FIG. 4, an exemplary graphical user interface isdisplayed that is suitable for entry of patient information inaccordance with the System mode of operation of the host application222. In particular, the displayed graphical display corresponds to auser (patient) data entry sub-screen under the System mode. While thehost 100 supports input of data using traditional keyboard, in anembodiment of the invention, the user enters, edits, and/or deletespatient information via a touch screen keyboard called up by selectingthe keyboard button 400. Turning briefly to FIG. 5, in response to auser selecting the keyboard button 400, the graphical user interfacedepicted in FIG. 4 is modified to include a touch screen keyboard 500.Alternatively, keyboard 500 is provided automatically. The informationentered will persist for the duration of the current session. ThePatient/System Information Display area (the first region 300) reflectschanges in corresponding fields.

FIG. 6 comprises an exemplary system sub-screen under the System mode.The user enters relevant system information, e.g., customer/institutionname 602, time/data 603, printer 604, LAN connection, local data storage606, and/or a Doppler audio volume 608. The system sub-screen depictedin FIG. 6 preferably also includes a button/control 610 enabling a userto initiate a system self-test. The user specifiedinformation/configuration persists indefinitely and spans multiplepatient sessions. The Patient/System Information Area (the first region300) reflects changes entered via this interface.

FIG. 7 comprises an exemplary system setup sub-screen 700 under theSystem mode of the host application 222. While the system setupinterface enables a user to modify default settings, the new defaultsettings are stored in a non-volatile file, persist indefinitely, andspan multiple patient sessions. The default settings are applied onsystem startup and reapplied via a reset button. As depicted in FIG. 7,the system setup sub-screen includes a new patient button 702 thatinvokes an interface enabling a user to enter new default setting for anew patient. A save patient study button 704 enables a user to store asession to a persistent device. A recall button 706 invokes an interfaceenabling a user to review and recall stored sessions. A reset systembutton 708 when selected, resets system information to default settings.A series of service selection buttons 710 enable a research mode ofoperation of the host system 100, enable data logging, commencediagnostics on the host 100, and enable selection of parametersdisplayed. A Cath Lab ID 712 allows the specification of a previouslystored particular configuration/setup based, for example, upon aparticular catheter lab within which the host 100 is to be used.However, the Cath Lab ID 712 field can be used to recall settings of anyparticular previously stored configuration/set up of the host 100. Amean period field 714 allows an operator to designate the number ofcardiac cycles that are used to calculate a single average value (e.g.,Average Peak Velocity).

FIG. 8 comprises an exemplary network communications setup sub-screen800. In the exemplary embodiment, the sub-screen enables a user toprovide information regarding report storage and transfer, connectivity,and format. In the exemplary embodiment a user interfaces to a DICOM(Digital Imaging and Communication in Medicine, an exemplary format fordata exchange between two different systems) compliant informationmanagement system via the DICOM sub-screen 800 interface of the systemmode of the host application 222. Other services provided by the DICOMsub-screen interface include transferring images to a remote DICOMarchive and recalling images from the remote DICOM archive. The fieldsof the sub-screen 800 include a patient name 802, an application entitytitle 804 for specifying the DICOM nodes with which the host 100communicates, a TCP port field 805 specifies a port through whichcommunications will take place, an Internet protocol address 806identifying the address of the computer on the network with which thehost 100 communicates, local DICOM storage location 808 specifies thelocal directory where the host 100 stores DICOM files, a browse button810 launches a well known utility to search within the host 100'sdirectory structure or create a new directory, storage file format 812enables a user to select a file storage format (e.g., DICOM,proprietary, etc.), and a configure button 814 launches configuration ofthe communications based upon the specified field data.

An exemplary set of interfaces associated with the system(administrative) mode of operation of the host system 100 including thehost application 222 has been described. Attention is now directed to aset of diagnostic modes of operation of the host system 100, and moreparticularly the display interfaces associated with illustrativepressure, flow and combination modes of operation. With reference toFIG. 9, the host application 222 includes a pressure mode setupsub-screen 900 that enables a user to specify particular displayattributes associated with a display sub-screen (see FIG. 10). Thepressure setup sub-screen 900 preferably provides the user with inputfeatures to customize the operation of the pressure mode.

The illustrative pressure mode setup sub-screen 900 includes a set oflow and high level input calibration controls 902 a and 902 b enabling auser to calibrate a pressure sensor in a variety of ways. The zerobutton in the calibration control displays 902 a and 902 b facilitatesestablishing a zero reference for the pressure sensor and a zero outputlevel reference for any external instruments. Zero level calibration isperformed by applying a zero pressure (ambient) and selecting the zerobutton on the calibration controls 902 a and 902 b. By way of example,low level input calibration is achieved through the low level inputcalibration control 902 a by applying a low pressure input, settingadjusting the scale value to the input pressure, and then pressing theset button. A high level input calibration is achieved through the highlevel input calibration control 902 b by applying a high pressure input,setting adjusting the scale value to the input pressure, and thenpressing the set button.

Though not shown in FIG. 9, the low and high pressure calibration isalternatively performed by pressing the button labeled “scale value” toenable calibration by establishing a zero pressure and providing a“slope” or calibration factor defining the relationship between changesto the input pressure and the input signal. The button labeled “scalevalue” actually toggles the calibration mode, and in response thecalibration display 902 a or 902 b converts to a calibration factormode. Rather than supplying an actual pressure, instead a calibrationfactor expressed in terms of micro-volts per mmHg is entered byadjusting a displayed value and then pressing the set button.

The pressure mode setup sub-screen 900 also includes a distal inputnormalization control 903 for normalizing input pressure measurementsfrom a distal pressure sensor via touch screen button controls.Normalization is the matching of the guide wire pressure sensor readingwith an aortic pressure. Normalization is achieved by bringing thepressure sensor to an appropriate location and selecting thenormalization button. This establishes a new value for the aorticpressure that is used to determine various calculated/displayed outputparameter values, including FFR. A distal sensor zero reference isestablished by selecting the zero button in the distal inputnormalization control 903 while applying a zero pressure reference.

The pressure mode setup sub-screen 900 also includes a set of venouspressure controls 904 including a venous pressure source control andvenous pressure adjust (up/down) controls. A mean venous pressure valueenables computing an FFR. The mean venous pressure may be input from atransducer via an external monitor or by a user preset value. Selectingthe venous pressure source button on the setup sub-screen 900 togglesthe source. Selecting ‘External’ designates the venous pressure sourceas a patient-applied transducer through an external monitor. Selecting‘Preset’ allows the user to enter an assumed value. Selecting theup/down controls increases/decreases the preset value accordingly. Thepreferred range of values for the venous pressure is about 0-50 mmHg.

An analog output offset adjust 906 provides an interface for a user toadjust the offset and the pressure high level analog output of the hostsystem 100. The user can increase or decrease the output via the userinterface. The output displays the current output adjustment level viathe user interface. The analog output is modified accordingly. Change iseffected by selecting the Up/Down arrow buttons adjacent to the OffsetAdjust display to increase/decrease the value accordingly. The valuewill change, for example, in steps of 1 mmHg. The preferred range ofvalues is about −30 to 330 mmHg.

The setup sub-screen 900 also includes maximum/minimum scaling presets908 for both distal and proximal pressures. An on/off buttonenables/disables an autoscaling feature of the host graphical outputdisplay for the proximal and distal pressures. When autoscaling isactivated, the scale of the output display expands as needed to handlean increased range of output pressures. A toggle button displayed in the“adjust” state for both proximal and distal scaling, enables manualadjustment of the maximum, and minimum scale values using the up/downarrow buttons. The pressure graph depicted in FIG. 10 in the displaysub-screen for the pressure mode reflects the designated scales.

Turning to FIG. 10, an exemplary pressure mode display sub-screen 1000displays data and pressure mode controls. The data driving the pressuredisplay is supplied by the pressure component 226 of the set ofMeasurement processing components 224 identified in FIG. 2. Theexemplary pressure mode display sub-screen 1000 includes a pressurewaveform graph 1002 including multiple pressure waveforms includingdistal, venous, and aortic pressure waveforms. A run/freeze control 1004stops and starts scrolling. A cursor/position control 1006 facilitatessearching a waveform. A calculation mode control 1008 includes a firstbutton for selecting a pressure calculation mode (e.g., distal/proximalgradient, distal/proximal ratio, normalized pressure ratio (NPR), andfractional flow reserve (FFR)) and a second button to search for peaks(visible only in FFR mode and used to detect peak hyperemic responseafter injecting a hyperemic agent). When the calculation mode control1008 is selected, it changes to a next one of the available types ofcalculation modes. The exemplary pressure display sub-screen 1000 alsoincludes a set of instantaneous/current measurement digital displays1010 including: distal pressure, aortic pressure, venous pressure, and aselected calculated value (e.g., distal-to-proximal gradient,distal-to-proximal ratio, NPR, FFR). A print button 1012 initiatesprinting a set waveforms recorded during a session. Recording of thewaveforms is toggled on/off by means of the record button 1014.

In the illustrated display, gradient calculation mode has been selected.In an exemplary embodiment, a gradient output is measured by taking adifference between pressures before (e.g., aortic) and after a partiallyblocked vessel. The distal-to-proximal ratio is calculated by dividingthe distal pressure by the proximal pressure. The normalized pressureratio is calculated by subtracting the venous pressure from the distaland proximal pressures and then taking their ratio. The FFR value iscalculated by taking the normalized pressure ratio at the peak hyperemicresponse. Pressure gradients/ratios across a heart valve are alsoprovided in association with yet another potential calculated valuerendered by the host 100.

Next, an exemplary set of user interfaces are show depicted that areassociated with a flow mode of operation of the host 100 and hostapplication 222. The flow mode graphical user interface is subdividedinto a number of sub-screens illustratively depicted by way of exampleherein. With reference to FIG. 11, a setup screen 1100 provides the userwith interface setup features to select and customize the operation ofthe flow mode of operation of the host 100. The flow setup includescontrols to set for example: Doppler audio volume and balance 1102—for aset of stereo speakers, a signal threshold 1104—via an on/off button anda threshold adjust, and velocity range 1106—similar to pressure in thata user can select either auto ranging or manually adjust the maximum onthe scale in the case where the auto ranging is shut off. Aconfiguration button 1108 toggles between coronary and peripheral arteryconfigurations to take into consideration the delay of velocity changesin relation to an ECG signal.

Trend setup controls 1110 set velocity scale and time base scale for atrend output. Furthermore, the trended parameter, average peak velocityor diastolic/systolic velocity ratio, is selected via the trend setupcontrols 1110. Other exemplary controls for the flow display modeinclude a sweep speed 1112 (selects the scrolling speed of the spectraldisplay from 3 speeds: slow, medium, or fast), zero offset 1114 (selectsthe zero velocity baseline position from 3 locations: low, medium, orhigh), and a flow direction 1116 (select the direction of flow to bedisplayed above the baseline from 2 bearings: antegrade or retrograde).A user can also optionally designate whether to display a blood pressuretrace 1118, ECG trace 1119. A user also selectively activates a noisefilter 1120. A calibration section 1122 allows a user to enable/disablean output calibration signal and select the particular waveform forperforming the calibration.

With reference to FIGS. 12 a-e, a set of illustrative examples of a flowdisplay are provided in accordance with two primary flow sensingconfigurations, coronary and peripheral—as designated by theconfiguration button 1108 on the flow setup sub-screen depicted in FIG.11. A flow operation sub-screen 1200 is displayed in its depicted statewhen a CFR operation button 1201 button is selected. In response, amulti-partitioned waveform display depicts a full wave form graph 1202as well as two smaller waveform display output segment graphs 1204 and1206 corresponding to the base waveform and peak wave form (underhyperemic conditions). The designation of the time frame in which datais gathered and displayed within the graphs 1204 and 1206 is determinedby pressing the base/peak button 1208 a first time to acquire the basereadings and then pressing the base/peak button 1208 a second time toacquire the peak readings.

The graphs 1202, 1204 and 1206 display flow velocity (based upon flowvelocity input data in the form of Doppler spectral arrays), measured ina variety of ways (e.g., average peak velocity, mean peak velocity andflow velocity). At each point in time, a set of grayscale values areassigned to each representative frequency component of the display.Intensity is assigned to points along a same time slice on the graphbased upon prevalence of the frequency indicative of blood flowvelocity. The display generates a set of markers associated withparticular sensed events. For example, the “S” represents the systolicpressure reading while the “D” represents the diastolic pressure readingin a cardiac cycle. A user can limit the displayed spectra by adjustingthe threshold background 1104 to exclude low level frequency components.Simultaneous with the velocity spectra, an instantaneous peak velocitytracking the blood flow velocity envelope's peak may also be displayed.

In the illustrative embodiment, instantaneous/current calculated valuesfor graphed parameters are digitally displayed as well in field 1210. Inparticular, field 1210 displays the instantaneous heart rate, averagepeak velocity (APV), and diastolic/systolic velocity ratio (DSVR).Additional sub-fields of field 1210 depict the APV and DSVR determinedduring a designated base time span and peak time span. Field 1210 alsodisplays the CFR calculated from the base and peak values. An optimalwire position indicator 1212 visually prompts a user to move the wire toobtain optimal placement positioning. A run/freeze button 1214 startsand stops scrolling of the displayed waveforms, and a cursor 1215 allowsscrolling within the previously displayed sections of the waveforms. Aprint button 1216 enables the printing of the waveforms. A record button1218 toggles a data/waveform recorder between an active/inactive loggingstate.

Having described an exemplary interface associated with the CFR flowmode, attention is briefly directed to other coronary modes supported bythe exemplary host system 100. FIG. 12 b depicts the display of the hostsystem 100 when a user selects the proximal/distal button 1220 while inthe coronary flow configuration. Instead of the base/peak button 1201, aproximal button 1222 and a distal button 1223 are displayed.

The proximal button 1222 is selected to invoke pressure input processingby the host system 100 corresponding to a pressure observed proximal(before) a stenosis. The corresponding waveform is displayed upon agraph 1224. The distal button 1223 is selected to invoke pressure inputprocessing corresponding to a pressure observed distal (after) astenosis. The corresponding waveform is displayed upon a graph 1226.

The output display depicted in FIG. 12 b includes instantaneous/currentcalculated values for graphed parameters in field 1228. In particular,field 1228 displays the instantaneous heart rate, average peak velocity(APV), and diastolic/systolic velocity ratio (DSVR). Additionalsub-fields of field 1228 depict the APV and DSVR determined for proximaland distal pressure readings. Field 1228 also displays theproximal/distal ratio calculated by the host 100 from the observedproximal and distal pressures.

FIG. 12 c depicts a graphical output display rendered in accordance withtrend calculations supported by the host system 100. When the trendoperation is selected, the host system 100 calculates an average flowvelocity value (e.g., APV, DSVR, etc.) over a period of time (e.g., acardiac cycle) and visually renders the value in the form of a graph1230. The trend mode is entered when a user selects a trend button 1231.In response, an APV button 1232 and a DSVR button 1234 are displayed.Based upon a user's selection, the calculated and displayed average iseither an APV or a DSVR. It is noted that the above two trend parametersare merely exemplary as those skilled in the art will readily appreciatethat other input/calculated are suitable for trend calculation, displayand analysis.

With continued reference to FIG. 12 c a set of instantaneous/currentcalculated values for graphed parameters are digitally displayed infield 1236. The output parameters displayed in field 1236 are the sameas the ones depicted in field 1210 in FIG. 12 a. However, the BASE, Peakand CFR parameters are not calculated by the host 100 while trendanalysis is occurring. Rather, these parameters are retrieved, if theyexist, from previous calculations rendered when the user selects the CFRbutton 1201. The base value is marked in the trend graph 1230 with a“B”, the peak value with a “P”, and the starting point of the peaksearch with an “S”. The time scale of the trend graph 1230 is on theorder of one or multiple minutes. The time scale of the ECG graph abovethe trend graph is on the order of seconds.

Turning now to FIGS. 12 d and 12 e, graphical display outputs areillustratively depicted for two exemplary peripheral operationssupported by the host 100. These two sub-screens of the flow modegraphical display 1200 are entered by selecting the peripheralconfiguration through the coronary/peripheral configuration button 1108on the flow setup sub-screen depicted in FIG. 11. The peripheralconfiguration takes into account that, in peripheral arteries, a flowvelocity signal lags an ECG signal, and therefore the peripheralconfiguration introduces a time shift to account for the lag.

FIG. 12 d illustratively depicts the display 1200 when the ratio button1240 is selected while the host system 100 is in the peripheral flowconfiguration. A graph 1242 displays a continuous graph depictingcalculated flow velocity. A base flow velocity graph 1244 is renderedfrom data collected by the host system 100 after a base/peak button 1246is selected a first time. A peak flow velocity graph 1248 is renderedfrom data obtained after the base/peak button 1246 is selected a secondtime.

In the illustrative embodiment, instantaneous/current calculated valuesfor graphed parameters are digitally displayed as well in field 1250. Inparticular, field 1250 displays the instantaneous heart rate, APV, andmean peak velocity (MPV). Additional sub-fields of field 1250 depict theAPV and MPV determined during a designated base time span and peak timespan. Field 1250 also displays a ratio calculated from the base and peakvalues.

FIG. 12 e illustratively depicts the display 1200 when the trend button1252 is selected while the host system 100 is in the peripheral flowconfiguration. The two snapshot graphs 1244 and 1248 are replaced by asingle trend graph 1254. In the illustrative embodiment,instantaneous/current calculated values for graphed parameters aredigitally displayed as well in field 1256. In particular, field 1256displays the instantaneous heart rate, APV, and mean peak velocity(MPV). Additional sub-fields of field 1256 depict the APV and MPVdetermined during a designated base time span and peak time span. Field1256 also displays a ratio calculated from the base and peak values.However, the displayed Base, Peak and ratio values in field 1256, areprovided from the previously described ratio operation described withreference to FIG. 12 e.

Yet another exemplary mode of the multiple interface modes is acombination mode that provides data from multiple sensors in a singlegraphical interface. In the illustrative example, no new signal inputtypes are needed to carry out the illustrative combination type ofgraphical display interface. In alternative embodiments, the combinationmode includes additional sensor input types such as, for example, atemperature input or a position sensor. FIG. 13 provides an exemplarycombination mode display in which flow and pressure measurements arecombined to render two side-by-side scrolling graphs depicting sensedflow and pressure parameters during an invasive diagnostic procedurewherein a flexible elongate member such as a guide wire, configured as acombination device (in this particular case including both a pressuresensor and a Doppler flow sensor) is inserted into a patient. Suchcombination devices, used in association with the combination outputprovide a desirable environment in which to calculate fractional flowreserve (FFR) using pressure readings, and coronary flow reserve (CFR)using flow readings. However, it is possible to utilize the presentsystem to make CFR and FFR measurements using non-combination devices,i.e. using multiple known single sensor devices.

Referring now to FIG. 13, the combination mode display screen 1300includes a first graph 1302 of sensed pressure and a second graph 1304of flow output parameters such as, for example, Doppler spectral arrays,average peak velocity and flow volume. Digital displays are providedthat illustratively indicate instantaneous measurements for distalpressure 1306, a pressure calculation (based upon selected calculationvia button 1316) such as gradient pressure 1308 (but also displays FFRor other calculated pressures), heart rate 1310, average peak flowvelocity 1312 and mean peak flow velocity 1314.

A CFR/Trend button 1320 provided a user the capability of selecting aCFR operation or trend operation in association with the acquisition offlow data. A flow velocity button 1321 enables selection of a flowvelocity output mode. As disclosed previously in FIGS. 10 and 12 a-e thescreen 1300, in an embodiment of the invention, reconfigures inassociation with a user's selection of the various selectable operationsand calculations supported by the combination mode of the host 100.

The combination screen 1300 also preferably includes scroll controls inthe form of scrolling arrows 1322 that enable a user to scroll forwardand back along the graphical output. A freeze/run toggle button 1324enables/disables scrolling of the graphs 1302 and 1304. A print button1326 initiates printing a session (or portion thereof). A record button1328 commences and halts recording session data in a toggling manner.

In addition to the touch screen controls, the host 100 preferablysupports interactive remote control/selection of the various displaycomponents depicted in the exemplary graphical user interface displaysdescribed herein above.

Having described a set of exemplary graphical user interfaces associatedwith a host system 100 embodying the present invention, attention isdirected to FIG. 14 which depicts a flowchart summarizing an exemplaryset of steps for carrying out a coronary flow reserve (CFR) measurement.Initially, a user selects the flow interface mode of the hostapplication 222. Thereafter, during step 1400 the user presses the CFRbutton 1201 on the display screen to measure CFR. In response duringstep 1402 the graph area of the screen 1200 vertically partitions intoupper and lower halves. The upper half graph 1202 displays the real-timevelocity spectra presently measured by the Doppler sensor. The lowerhalf of the graph display area is divided horizontally into two sectionsfor displaying snapshots of the spectral display taken from the upperpartition. The lower left area contains baseline graph 1204, and thelower right area is reserve for a peak response graph 1206.

During step 1404, a user presses the BASE/PEAK button 1208 on thedisplay 1200 to save the baseline spectral display. A snapshot of thereal-time spectral display is transferred to the lower left (baseline)graph 1204 of the display during step 1406.

Next, at step 1408 a hyperemic agent is injected into the patient. Atstep 1410 the BASE/PEAK button 1208 is selected a second time. Inresponse, at step 1412 the host application 222 automatically begins asearch for a peak hyperemic response (maximum average peak velocity(APV)—where the APV is determined by averaging the instantaneous peakvelocity (IPV) over a cardiac cycle). During step 1414 a snapshot of thereal-time spectral display is transferred to the lower right (peak) areaon the graph 1202. During steps 1416 and 1418 the CFR ratio isperiodically recalculated based upon the maximum APV found during thesearch and the current maximum ratio is displayed digitally in field1210. Pressing the BASE/PEAK button 1208 a third time manuallyterminates the search. The search is automatically terminated if 5consecutive seconds have elapsed and the maximum APV has not changed.The last CFR ratio value is held in the display as the process fordetermining the CFR ratio ends.

Turning now to FIG. 15, an exemplary set of steps for carrying out afractional flow reserve (FFR) determination using the host system 100 ina pressure mode and a guide wire including a pressure transducer issummarized. Initially, during step 1500 the FFR mode is selected via thecalculation mode button of the calculation mode control 1008. A bloodpressure sensor is placed in position to measure distal pressure withina vessel. Aortic pressure is simultaneously monitored using an aorticpressure sensor. Thereafter, during step 1501 or 1502 (based upon thespecifically selected FFR mode—intracoronary or intravenous) thehyperemic agent is either injected in the blood vessel underinvestigation or administered intravenously. The peak search button ofthe calculation mode control 1008 (displayed only for FFR mode) isselected to observe the hyperemic response of the vessel during step1504. The host application 222 displays a “searching” prompt at step1506 until it locates a peak response while carrying out a search duringstep 1508. When the peak is detected, the FFR value is displayed duringstep 1510 on the display 1000.

The pressure mode of operation of the host application 222 preferablyalso supports determination of a proximal/distal ratio. The set ofexemplary steps for such a procedure are depicted in FIG. 16. Initiallyduring step 1600 the P/D mode is selected via the calculation modebutton of the calculation mode control 1008. This results in a splitscreen similar to the one described above for the CFR ratiodetermination process summarized in FIG. 14. Next, at step 1602 aftermoving a pressure sensor to a proper location within a vessel to obtaina proximal pressure reading, a user selects a proximal button that isdisplayed when the ratio calculation operation is selected. In response,during step 1604 the host application 222 stores the current proximalimage in the lower left quadrant of the graph 1002 (in a split screensimilar to the one displayed for CRF operations). Next, a pressuresensor of the guide wire is moved to a point beyond (distal to) astenosis during step 1606. At step 1608 a distal display button renderedwithin the calculation mode control 1008 area is selected on thegraphical display screen 1000. In response, during step 1610 the hostapplication 222 stores the current distal image in the lower rightquadrant of the graph 1002. At step 1612 the proximal/distal pressureratio is calculated based upon the stored inputs at steps 1604 and 1610,and during step 1614 the P/D ratio is displayed on the display 1000. Itis noted that the ordering of taking the proximal and distal readings isnot important to carry out the P/D ratio determination. In fact, in asystem wherein two pressure sensors are simultaneously placed in properlocations to take the proximal and distal readings, the readings aretaken at substantially the same time.

Having described a number of exemplary applications of the host system100 and its multipurpose, multimode architecture the breadth ofpotential configurations/applications of this architecture isdemonstrated through two additional uses that involve the incorporationof a sensor orientation/displacement signal and a temperature sensorsignal received by the PCI card 112 of the host system 100. The hostsystem 100, for example, receives pressure sensor signals and a sensordisplacement signal enabling the host system 100 to render a map ofpressure variations along a vessel. The resulting substantiallyreal-time graphical display can be used, for example, to locate astenosis or guide optimal placement of treatment of a vessel blockage.In yet another application supported by the host system 100, a positionsensors identifying angular displacement as well as displacement alongthe length of a vessel are integrated, by the host system, with atemperature sensor mounted upon a flexible elongate member to provide atemperature map for the walls of a vessel to identify lesions. Such mapis created by the host system 100 by rotating a temperature sensorplaced against the vessel wall and drawing the temperature sensor backalong the vessel. The host system 100 receives and integrates thesignals provided by the temperature and position sensors and renders acorresponding map.

Illustrative embodiments of the present invention and certain variationsthereof have been provided in the Figures and accompanying writtendescription. Those skilled in the art will readily appreciate from theabove disclosure that many variations to the disclosed embodiment arepossible in alternative embodiments of the invention. Such modificationsinclude, by way of example, modifications to the form and/or content ofthe disclosed functions and functional blocks of the disclosedarchitecture, the measurements processed by the host system, thecalculations arising from the measurements, the methods for settingmodes and acquiring the measurements. Additionally, imaging data, suchas Intravascular Ultrasound, Magnetic Resonance Imaging, OpticalCoherence Tomography, etc., may be obtained, analyzed, and/or displayedupon the multipurpose application interface supported by the host systemdescribed hereinabove. The present invention is not intended to belimited to the disclosed embodiments. Rather the present invention isintended to cover the disclosed embodiments as well as others fallingwithin the scope and spirit of the invention to the fullest extentpermitted in view of this disclosure and the inventions defined by theclaims appended herein below.

What is claimed is:
 1. A method of performing an invasive cardiovascularprocedure using multiple invasive sensor types, the method comprising:communicatively coupling a first invasive cardiovascular sensingcomponent to a multi-purpose host system; communicatively coupling asecond invasive cardiovascular sensing component to the multi-purposehost system; positioning at least a portion of the first invasivecardiovascular sensing component within a vessel of a patient;positioning at least a portion of the second invasive cardiovascularsensing component within the vessel of the patient; utilizing a userinterface of the multi-purpose host system to control operation of thefirst invasive cardiovascular sensing component to cause the firstinvasive cardiovascular sensing component to obtain data related to afirst invasive cardiovascular parameter while positioned within thevessel of the patient; utilizing the user interface of the multi-purposehost system to control operation of the second invasive cardiovascularsensing component to cause the second invasive cardiovascular sensingcomponent to obtain data related to a second invasive cardiovascularparameter while positioned within the vessel of the patient, the secondinvasive cardiovascular parameter being different than the firstinvasive cardiovascular parameter; utilizing a first processingcomponent of the multi-purpose host system to process the data relatedto the first invasive cardiovascular parameter to produce valuesassociated with the first invasive cardiovascular parameter for displayon the user interface of the multi-purpose host system; and utilizing asecond processing component of the multi-purpose host system to processthe data related to the second invasive cardiovascular parameter toproduce values associated with the second invasive cardiovascularparameter for display on the user interface of the multi-purpose hostsystem.
 2. The method of claim 1, wherein the data related to the firstinvasive cardiovascular parameter is processed by the first processingcomponent independently from the data related to the second invasivecardiovascular parameter being processed by the second processingcomponent.
 3. The method of claim 1, wherein the first and secondinvasive cardiovascular parameters are selected from the group ofparameters consisting of: pressure, flow velocity, flow volume, pH,ultrasound images, light-based images, and tissue characterization. 4.The method of claim 1, wherein the first invasive cardiovascular sensingcomponent is secured to a first flexible elongate member and whereinpositioning the first invasive cardiovascular sensing component withinthe vessel of the patient includes positioning the first flexibleelongate member within the vessel of the patient.
 5. The method of claim4, wherein the second invasive cardiovascular sensing component issecured to the first flexible elongate member and wherein positioningthe second invasive cardiovascular sensing component within the vesselof the patient includes positioning the first flexible elongate memberwithin the vessel of the patient.
 6. The method of claim 4, wherein thesecond invasive cardiovascular sensing component is secured to a secondflexible elongate member and wherein positioning the second invasivecardiovascular sensing component within the vessel of the patientincludes positioning the second flexible elongate member within thevessel of the patient.
 7. The method of claim 1, wherein the firstinvasive cardiovascular parameter is a pressure within the vessel. 8.The method of claim 7, wherein the second invasive cardiovascularparameter is imaging data representative of the vessel.
 9. The method ofclaim 8, wherein the second invasive cardiovascular parameter isultrasound imaging data representative of the vessel.
 10. The method ofclaim 8, wherein the second invasive cardiovascular parameter is OCTimaging data representative of the vessel.
 11. The method of claim 7,wherein processing the data related to the first invasive cardiovascularparameter includes calculating a fractional flow reserve (FFR).
 12. Amethod of performing an intravascular procedure using multiple invasivesensor types, the method comprising: obtaining a first elongateintravascular device sized and shaped for positioning within a vessel ofa patient, the first elongate intravascular device including a firstintravascular sensing element configured to obtain data related to afirst intravascular parameter; obtaining a second elongate intravasculardevice sized and shaped for positioning within the vessel of thepatient, the second elongate intravascular device including a secondintravascular sensing element configured to obtain data related to asecond intravascular parameter, the second intravascular parameter beingdifferent than the first intravascular parameter; coupling the first andsecond elongate intravascular devices to a multi-purpose host systemsuch that the first and second intravascular sensing components are incommunication with a processing system of the multi-purpose host system,wherein the multi-purpose host system is configured to control operationof the first and second intravascular sensing components based on inputto a user interface of the multi-purpose host system and wherein theprocessing system is configured to process the data related to the firstand second intravascular parameters obtained by the first and secondintravascular sensing elements.
 13. The method of claim 12, wherein thefirst intravascular parameter is a pressure within the vessel and thesecond intravascular parameter is imaging data representative of thevessel.
 14. A method of performing an intravascular procedure utilizinga pressure sensor and an imaging element to obtain pressure data andimaging data within a vessel of a patient, the method comprising:obtaining a first elongate intravascular device sized and shaped forpositioning within the vessel of the patient, the first elongateintravascular device including a pressure sensor configured to obtaindata related to a pressure within the vessel of the patient; obtaining asecond elongate intravascular device sized and shaped for positioningwithin the vessel of the patient, the second elongate intravasculardevice including an imaging element configured to obtain imaging datarepresentative of the vessel of the patient; coupling the first elongateintravascular device to an external interface of a multi-purpose hostsystem such that the pressure sensor is in communication with aprocessing system of the multi-purpose host system, wherein themulti-purpose host system is configured to control operation of thepressure sensor by transmitting signals through the external interfaceto obtain data related to the pressure within the vessel of the patientand wherein the processing system is configured to process the datarelated to the pressure within the vessel received through the externalinterface to produce values associated with the pressure within thevessel for display on a user interface of the multi-purpose host system;and coupling the second elongate intravascular device to the externalinterface of the multi-purpose host system such that the imaging elementis in communication with the processing system of the multi-purpose hostsystem, wherein the multi-purpose host system is configured to controloperation of the imaging element by transmitting signals through theexternal interface to obtain imaging data representative of the vesselof the patient and wherein the processing system is configured toprocess the imaging data representative of the vessel received throughthe external interface to produce images of the vessel for display onthe user interface of the multi-purpose host system.
 15. The method ofclaim 14, further comprising: positioning the first elongateintravascular device within the vessel of the patient; obtaining datarelated to the pressure within the vessel of the patient with thepressure sensor while the first elongate intravascular device ispositioned within the vessel of the patient; positioning the secondelongate intravascular device within the vessel of the patient; andobtaining imaging data representative of the vessel of the patient withthe imaging element while the second elongate intravascular device ispositioned within the vessel of the patient.
 16. A method of performingan invasive cardiovascular procedure using multiple sensor types, themethod comprising: positioning portions of first and second invasivecardiovascular sensing components within a patient; communicativelycoupling the first and second invasive cardiovascular sensing componentsto a control system; utilizing a user interface of the control system tocontrol operation of the first and second invasive cardiovascularsensing components to cause the first invasive cardiovascular sensingcomponent to obtain data related to a first invasive cardiovascularparameter and to cause the second invasive cardiovascular sensingcomponent to obtain data related to a second invasive cardiovascularparameter, the second invasive cardiovascular parameter being differentthan the first invasive cardiovascular parameter; and utilizing aprocessing system associated with the control system to process the datarelated to the first and second invasive cardiovascular parameters toproduce values associated with the first and second invasivecardiovascular parameters for display on the user interface of thecontrol system.
 17. The method of claim 16, wherein processing the datarelated to the first and second invasive cardiovascular parametersincludes processing the data related to the first invasivecardiovascular parameter independently from the data related to thesecond invasive cardiovascular parameter.
 18. The method of claim 16,wherein the first and second invasive cardiovascular parameters areselected from the group of parameters consisting of: pressure, flowvelocity, flow volume, pH, ultrasound images, light-based images, andtissue characterization.
 19. The method of claim 16, wherein the firstinvasive cardiovascular sensing component is secured to a first invasivecardiovascular device and wherein positioning the first invasivecardiovascular sensing component within the patient includes positioningthe first invasive cardiovascular device within a vessel of the patient.20. The method of claim 19, wherein the second invasive cardiovascularsensing component is secured to the first invasive cardiovascular deviceand wherein positioning the second invasive cardiovascular sensingcomponent within the patient includes positioning the first invasivecardiovascular device within the vessel of the patient.
 21. The methodof claim 19, wherein the second invasive cardiovascular sensingcomponent is secured to a second invasive cardiovascular device andwherein positioning the second invasive cardiovascular sensing componentwithin the patient includes positioning the second invasivecardiovascular device within the vessel of the patient.
 22. The methodof claim 21, wherein the first invasive cardiovascular parameter is apressure within the vessel.
 23. The method of claim 22, wherein thesecond invasive cardiovascular parameter is imaging data representativeof the vessel.
 24. The method of claim 23, wherein the second invasivecardiovascular parameter is ultrasound imaging data representative ofthe vessel.
 25. The method of claim 23, wherein the second invasivecardiovascular parameter is OCT imaging data representative of thevessel.
 26. The method of claim 23, wherein processing the data relatedto the first invasive cardiovascular parameter includes calculating afractional flow reserve (FFR).
 27. The method of claim 26, wherein theimaging data representative of the vessel is generated by a light-basedimaging technique.
 28. The method of claim 26, wherein the imaging datarepresentative of the vessel is generated by optical coherencetomography (OCT).
 29. The method of claim 26, wherein the imaging datarepresentative of the vessel is suitable for characterizing a tissue ofthe vessel.
 30. The method of claim 16, further comprising guidingplacement of a treatment based on a display of the user interface.